This semester we were given a group project (3 or 4 people). We had to make a machine to bend plexiglass (PMMA). More specifically, we had to bend plexiglass in a freeform. Therefore, we were not allowed to use a mold or a simple bending mechanism. Later we decided to make spirals by softening and twisting the plexiglass. From now on we called our machine the 'PlexiTwister'

We went through different stages to improve the PlexiTwister. We made a CAD drawing and several prototypes, but finally we made one last definitive model.

We hope you find this tutorial of 'how to make this plexi bend machine' useful. There is a lot of visual content so it's easy to make it for yourself. Now, I can only say..let's get started!

Project made by:

Natan Doms, Stijn Van Damme, Pieter-Jan Belles, Kenny Callewaert

Step 1: Tools & Material List

Materials needed:

• 4 MDF sheets, A2 format (594 x 420 mm), 6 mm
• 2 Roll bearings, inner diameter 6 mm, outer diameter 13 mm
• 4 Bronze bushings, inner diameter 8 mm, outer diameter 12 mm
• 2 Shafts, 8 mm x 600 mm
• 5 Shafts, 6 mmm x 80 mm
• Approximately 90 bolts and nuts, M3x16
• 12 bolts and nuts, M4x12
• 5 bolts and nuts M8x40
• 4 M2 bolts (for adjusting rings)
• 2 Adjusting rings, inner diameter 6 mm, outer diameter 10 mm
• 4 Adjusting rings, inner diameter 8 mm
• IR lamp, 650 W
• Electric switch, wire and power cord
• Aluminum sheet, approximately (200 x 300 mm)
• Aluminum rectangular bar (2 x 20 x 570 mm)
• 2 small 2 mm steel rod (approximately 10 mm long)

Tools needed:

• Lasercutter
• Basic handtools (like screwdrivers, ...)
• Woodglue & superglue

Step 2: Lasercutting

The first step is to cut the MDF sheets using a lasercutter. You can find the laserplans below.

Note: Make sure you select the right material and material thickness in the lasercutter settings.

Step 3: Assembly: the Frame

Step 4: Assembly: Sliding Clamp

Step 5: Assembly: Cover Plate

Don't forget to make this twice!

Step 6: Assembly: Rotating Clamp

Step 7: Assembly: Handle

Step 8: Assembly: Reflection Plate

Step 9: Assembly: Lid

Step 10: Assembly: Montage of Subassemblies

Step 11: Testing

We started testing the machine after it was build and became some beautiful results. We also made a video to demonstrate the usage of the 'PlexiTwist'. So we came to the end of the instructable, we hope this was usefull for you.

Made by:

Natan Doms

Stijn Vandamme

Pieter-Jan Belles

Kenny Callewaert

Interesting idea however you need to understand the difference between melting and softening. In this project you are softening the material in order to twist it. Melting means to turn to liquid which is very difficult to do with PMMA using heat.
Yeah you're right, my mistake.

About This Instructable




More by NatanDoms:PlexiTwister Compressed Air Airplane 
Add instructable to: